The present invention relates to an apparatus for the sterilization and secondary packaging into cartons of arrays of blister packages, each of which contains at least one hydrophilic contact lens immersed in a sterile aqueous solution. More specifically, the invention is directed to an apparatus adapted to provide for the assembly of paired arrays of blister packages which are suitably interleaved and transported in batches of predetermined quantities within one or more trays. These trays are transported to a sterilization chamber for sterilizing the exterior surfaces of the arrays of blister packages, particularly the lens-containing interiors thereof, and from which the sterilized arrays of blister packages are then transported to a locale for implementing the secondary packaging thereof into sealable cartons. In addition to the foregoing, the invention is also directed to a method of sterilizing and implementing the secondary packaging into cartons of predetermined quantities of arrays of blister packages, each of which contains a hydrophilic contact lens immersed in a sterile aqueous solution, so as to provide a sterile environment for the arrays of blister packages.
The packaging of hydrophilic contact lenses in a sterile aqueous solution is well known in the contact lens manufacturing technology. Particularly, packaging arrangements of that type generally consist of so-called blister packages adapted to be employed for the storage and dispensing of the hydrophilic contact lenses for use by a medical practitioner or a consumer who intends to wear the contact lenses. Such hydrophilic contact lenses, which may be disposable after a single period of wear or short-term use, are inexpensively manufactured from suitable hydrophilic polymeric materials; for example, copolymers of hydroxyethylene methacrylate (HEMA) containing from about 20% to 90% or more of water, depending upon the polymer composition. These contact lenses are generally stored immersed in a sterile aqueous solution, ordinarily consisting of an isotonic saline solution, in order to prevent dehydration and to maintain the lenses in a ready-to-wear condition.
A blister package of the foregoing type normally comprises a base member which is molded from a suitable injection-molded or thermoformed plastic material; for instance a polyolefin, such as polypropylene, and incorporates a cavity adapted to house the contact lens in the aqueous solution. The cavity is sealingly closed by a label-forming cover, preferably in the form of a flexible multi-layered laminated foil or suitable fill structure to provide the so-called blister package. This type of packaging arrangement has found widespread use in view of the inherently advantageous storing properties thereof and easy-to-dispense nature of the package by simply peeling the foil from the base member enabling a user to gain ready access to the contact lens which is contained in the cavity of the base member. For example, a blister package which is adapted to provide a sterile sealed storage environment for a disposable, essentially single-use hydrophilic contact lens, which is normally worn for about 8-18 hours within any 24-hour period, wherein the lens is immersed in a sterile aqueous solution within the package is described in U.S. Pat. No. 4,691,820 to Martinez; which is assigned to the common assignee of the present application, and the disclosure of which is incorporated herein by reference.
In the above-mentioned U.S. patent, the blister package for storing and dispensing a hydrophilic contact lens includes an injection-molded or thermoformed plastic base portion or member incorporating a molded cavity which is surrounded by an outstanding planar flange extending about the rim of the cavity. A flexible cover sheet, such as a laminated foil is adhered to the surface of the flange so as to sealingly enclose the cavity in a generally liquid-tight manner. The surface of the covering foil may constitute a label and be imparted suitable printing indicia informative of the product stored in the blister package, the name and address of the manufacturer, and also incorporate various decorative designs and logos as desired; and also provide for changeable information, such as lot numbers, fitting parameters, expiration dates and the like in addition to the foregoing, such as may be required by FDA regulations.
At this time, a novel and unique concept has been developed through a design for packaging arrangements of the blister package type, particularly for the containment of hydrophilic contact lenses in a sterile aqueous solution, wherein a plurality of base members for such blister packages, each having a cavity for containing a hydrophilic contact lens in the sterile aqueous solution, are adapted to be positioned in a contiguous array and sealing covered by a single or unitary flexible cover sheet, the latter of which is preferably in the form of a multi-layered flexible laminate web having a foil or silicon oxide layer therein. In this instance, the laminated cover sheet is provided with weakening lines, preferably in the form of perforations, extending intermediate each of the respective base members so as to enable individual segments of the foil member to be detached along the weakening lines and in conjunction with the therewith associated base member separated from the remaining array when it is desired to gain access to the contact lens contained in the separated blister package without adversely affecting the integrity of the packaging. This type of arrayed multiple interconnected blister package structure enables the compact packaging of a plurality of such arrays, each possessing a specified number of contact lens-containing base members interconnected by a single flexible cover sheet, within the confines of a suitable sealed container, such as a rigid paperboard carton. In the carton there may be compactly stored a plurality of interleaved pairs of and superimposed arrays of blister packages wherein; for example, each array consists of five interconnected blister packages with each of the latter having a single disposable contact lens housed therein. The carton may store six superimposed arrays of blister packages, for a total of thirty contact lenses; or in effect, a 30-day supply of contact lenses for respectively one eye of a user, although it is possible to contemplate to provide for cartons storing a 5-, 10-, 15-, 20-, or 25-day supply of contact lenses, or even other quantities. A packaging arrangement for contact lenses of that type which is in the form of arrays of interconnected blister packages is disclosed in applicant's copending U.S. patent application Ser. No. 08/257,796, entitled "Packaging Arrangement for Contact Lenses", which is commonly assigned to the assignee of the present application and the disclosure of which is incorporated herein by reference.
The blister packages which are formed through the intermediary of this structure comprise a plurality of contiguously arranged injection-molded base members each containing a cavity for housing a hydrophilic contact lens in a sterile aqueous solution, and wherein the resultant array of such base members; for example, five (5) base members, is adapted to be sealingly covered and interconnected by a single multi-layered flexible laminated foil or web which also forms a common label, preferably of the type disclosed in applicant's copending U.S. patent application Ser. No. 08/106,386, filed Aug. 13, 1993, entitled "Method of Double-Sided Printing of a Laminate and Product Obtained Thereby" assigned to the common assignee of the present application, and the disclosure of which is incorporated herein by reference.
In the foregoing disclosure, the multi-layered laminated foil includes an outer layer of a plastic film material, such as a polyolefin and preferably polyester, which is adhesively bonded to the surface of a supporting metallic foil, such as aluminum, although a layer of silicon oxide could be utilized instead of the metallic foil, and in which the outer layer is double-sided printed; in effect, on both opposite surfaces. The surface of the outer plastic film layer which faces towards and is adhered to the metallic foil is imprinted with suitable indicia and legends which may consist of permanent information regarding the manufacturer and the product, logos, instructive material, and decorative and advertising indicia relative the product in the blister package; whereas the opposite or exterior surface of the outer plastic film material layer may include suitable changeable information, such as expiration dates, lot numbers, fitting parameters, lens power, and other data specific to the packaged product. The interior surface of the outer plastic film material layer, when desired, may be imprinted. through the intermediary of suitable lithographic printing, either in single color or multi-colors and also provided with an appropriate printed background; whereas the changeable information specific to the product which is imprinted on specific areas of the outwardly facing surface of the outer film layer, may be printed thereon through thermal transfer printing, as described in detail in the above-referenced copending U.S. patent application Ser. No. 08/106,386.